Abstract: A friction wheel includes a ring and bearing assembly, the friction ring extending from opposite sides of the bearing and having an inner facing surface; a hub surrounding an inner passage sized for receipt of the ring and bearing assembly, and the hub including an annular lip extending therefrom on opposite sides of the hub; at least one cap having an annular rim sized and configured for secured attachment to the annular lip, and each cap including an annular sleeve extending therefrom, and wherein the ring is sized for engaged receipt of the annular sleeve; raised elements on the annular sleeve sized and configured for a friction fit against the inner facing surface of the ring; and wherein relative rotation between the at least one cap and the ring requires a force sufficient to overcome the friction fit between the raised elements and the inner facing surface of the ring.

Abstract: The present invention concerns nestable shopping carts including a lifter mechanism allowing the rear wheels of each cart to rise when they are nested together in order to facilitate their displacements when forming a line and to limit the wear of rear wheels. The lifter system comprises the wheeled chassis of the cart having a front end section sloping downwardly from a line of junction. The chassis also comprises a rear cross-bar that may pass above the line of junction of a following similar cart. The lifter system can be easily modified to cancel its rising property in that it also comprises a height adapter removably connectable to the cross-bar for reducing, when connected to the cross-bar, the height of the bottom surface of the cross-bar causing the rear end of the chassis to lift when a following similar shopping cart is nested into the shopping cart.